Pockets in AL plate

I have to mill 32 round pockets into an AL plate. The pockets range from
2.125" dia. x .180" deep to 2.625" dia. x 1.80 deep. This plate will be a
mold for injecting Urethane into thin wire wheel brushes that are used to
clean grooves and such. This encapsulating process is done by another
company that is a trading partner and good friends. They just don't have
much machining capability. In return, I get a hot stamping machine that I
have good use for.
Very much like this:
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My first thought is to use a large end mill and do the center of the pocket
then enlarge the dia. with a boring head. Any other ideas?
Reply to
Tom Gardner
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If you don't have CNC capability, I think you're on the right track. I would mark the full dia and rough it out with the large end mill (not just the center) so that you minimize the passes with the boring head to final dia. With a CNC the circular interpolation would to it all in one setup with no fuss.
Reply to
Pete C.
If I had to make it on my manual machines, I'd subdivide the plate into pieces I could bore out on a lathe faceplate, to get a better surface finish than milling, and bolt them to a subplate.
I'd make some spares as replacements or to change the size mix.
jsw
Reply to
Jim Wilkins
Interesting concept. I see the pockets are .180 deep. Wonder if the largest pocket has an error on the depth? 1.80 deep? If they are ALL .180 deep, then you could bore the hole completely through and then reduce the rim to .180.
Paul
Reply to
Paul Drahn
If the depths are all 0.180" then I see if 0.187" is ok, then do them as through holes in a sheet of 3/16" plate, then bolt that to a backing plate. Saves all the agony of a good surface finish on the bottom of each pocket. Otherwise without cnc I think your approach is probably best.
----- Regards, Carl Ijames
I have to mill 32 round pockets into an AL plate. The pockets range from 2.125" dia. x .180" deep to 2.625" dia. x 1.80 deep. This plate will be a mold for injecting Urethane into thin wire wheel brushes that are used to clean grooves and such. This encapsulating process is done by another company that is a trading partner and good friends. They just don't have much machining capability. In return, I get a hot stamping machine that I have good use for.
Very much like this:
formatting link
My first thought is to use a large end mill and do the center of the pocket then enlarge the dia. with a boring head. Any other ideas?
Reply to
Carl Ijames
Tom asked:
Use as large an end mill as will fit in the hole with sufficient roughing clearance. Spiral-drill the holes in conventional milling (spiral drill gives a better finish in conventional than it does in climb). Then do a full-depth finishing pass in climb.
You can save tool life and a bit of time (by virtue of faster feed rates) if you pre-drill the hole as large and deep as permissible.
Lloyd
Reply to
Lloyd E. Sponenburgh
If you don't have CNC capability, I think you're on the right track. I would mark the full dia and rough it out with the large end mill (not just the center) so that you minimize the passes with the boring head to final dia. With a CNC the circular interpolation would to it all in one setup with no fuss. ______________________________________________________________
Yep, this is one of the few times I really crave CNC on my BP! If I could only justify it....
Reply to
Tom Gardner
If I had to make it on my manual machines, I'd subdivide the plate into pieces I could bore out on a lathe faceplate, to get a better surface finish than milling, and bolt them to a subplate.
I'd make some spares as replacements or to change the size mix.
jsw ___________________________________________________
That would be nice but the owner said no.
Reply to
Tom Gardner

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